Prismatic binocular.



PRISMATIG BINOCULAB.

(Application filed Feb. 20, 1900' \No Model'.

W INVENTOR TNES $551 a c/OHN He/myBn/zm/v Qflw 3 7 flylww ms HTTORNEYPF- UNITED STATES PATENT OFFICE.

JOHN HENRY BARTON, OF LONDON, ENGLAND, ASSIGNOR TO THE ROSS, LIMITED, OF SAME PLAOE.

PRISMATIC BINOCULAR.

SPECIFICATION forming part of Letters Patent No. 657,808, dated September 11, 1900.

Application filed February 20; 1900. Serial No. 5.917. (No model.)

T0 at whrmt it may concern:

Be it known that I, J on HENRY BARTON, a subject of the Queen of Great Britain and Ireland, and a resident of 3 North Side, Clapham Common, London, England, have invented certain new and useful Improvements in the Construction of Prismatic Binoculars, (for which a patent has been applied for in Great Britain, No.15,376, dated July 20, 1899,) which invention is fully set forth in the following specification.

The object of this invention is to construct prismatic binoculars in such a manner as to be very compact and simple and readily adjusted to obtain coincident images.

In order that this invention may be well understood, I will describe with reference to the accompanying drawings a construction in accordance therewith in which the arms at one end are affixed to the end plates so as to allow of adjustment; but it is to be understood that the arrangement at each end may be such as to allow of adjustment for obtaining coincident images or not, as may be desired.

Figure 1 is a plan, and Figs. 2 and 3 are views of the opposite ends. Fig. i is a sectional view on the line 4: 4, Fig. 3.

Ct represents the body parts of the instrument,and b represents the end p1ates,to which the aforesaid arms 0 (of any suitable shape and size) are affixed. The said arms 0 at the eyepiece end are shown as being formed in one with the end plates I), while the arms 0 at the object-glass end are shown as being provided with extensions 0 (of any suitable shape and size,) secured by screws d to the end plates. By making the clearing-holes for the screws in the extensions 0 larger than is actually necessary for the passage of the screws d through them, Figs. 3 and at, the aforesaid adjustment for the obtaining coincidence of the images can be made, the said extensions being clamped not quite tightly against the end plates b,the screws dbeing left somewhat loose. The adjustment can then be made by a slight movement of the bodies relatively to each other, (such slight move* ment being allowed by reason of the enlarged clearing-holes aforesaid in the extensions 0 and so soon as the adjustment is satisfactory the screws 01 are tightened, so that the arms are practically as rigidly secured to the plates as if they were in one therewith; but,if thought desirable, additionalscrews or steadying-pins may be placed in the extensions 0 engaging with the end plates b after the adjustment has been made and the screws (Z tightened up. The outer ends of each of the arms forminga pair at each end of the instrument are shown as being recessed and engaged together and' centered at 6, so that they can be turned, as on a hinge, for altering the distance between the eyepieces.

The movement for focusing of the two eyepieces can be done by turning the eyepiececarriers f on the tubes 9 in any well-known manner.

I claimas my invention A prismatic binocular having the body parts connected by arms affixed to the end plates and connected in pairs at each end so as to be capable of being turned as upon a hinge for adjustment of the distance apart of the eyepieces, one or more of the said arms being adjnstably affixed to the end plate or plates as to allow of slight adjustment of the body parts for obtaining coincident images, substantially as hereinbefore described.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

JOHN HENRY BARTON. Witnesses:

WILLIAM JAMES COSTIN, JOHN EDWARD NEWTON. 

